Jump to content

Stargazers Lounge Uses Cookies

Like most websites, SGL uses cookies in order to deliver a secure, personalised service, to provide social media functions and to analyse our traffic. Continued use of SGL indicates your acceptance of our cookie policy.



Advanced Members
  • Content Count

  • Joined

  • Last visited

Community Reputation

141 Excellent

About MeyGray3833

  • Rank
    Star Forming

Profile Information

  • Gender
  • Interests
    Astronomy, Astrophotography, Motor Racing, Cooking, Family
  • Location
  1. Ok, so the way you described it is how I set it up originally. I thought that I placed it wrong and added a 10mm spacer for giggles to see what would happen. Hard to get good star shape now. So, really this flattener is not suitable for a dedicated astro set up? If you want to dabble with a DSLR, all good. The other flattener that I have has a backfocus of 88mm plus 1 mm for filters. https://www.teleskop-express.de/shop/product_info.php/info/p2646_TS-Optics-PHOTOLINE-Full-Frame-APO-Corrector---Flattener-for-astrophotography.html This unit appears to be made with cameras other than DSLR's in mind.
  2. Your modesty is a virtue, William. I have not fitted the field stops at this stage, I am a little bit over the battle at the moment, so I've decided to capture a few images with what I have for the moment and digest all that has come to pass. In doing so, I have been contemplating the new flattener that I have aside for the scope and was thinking about back focus distances which got me to thinking about my current setup. Can someone interpret the specs on this page for the Flat IV particularly the recommended lens to chip distance and back focus recommendations. https://www.cyclopsoptics.com/flattener-reducer/william-optics-flat4-0-8x-reducer-flattener/ I take it that the 66-86 mean the numbers on the flattener adjustment and the back focus is the distance from the chip to the back of the flattener?
  3. Wow, when Olly said you were the expert on this, he was not kidding! Thank you so much for all your effort so far. I will certainly give that a try and report back with my results. Seeing as the weather is so hot and guiding is poor due to the wobbly sky, it is the right time of year to do this. It is going to be 43 here tomorrow, it is 36 today. Glad I'm not missing out on too much!
  4. Thanks everyone for your help. As it stands today, I am defeated! William was right, I fear. After all the messing about and travel time as my obs is remote (120km round trip), I think I must concede that it is a reflection between the flattener and the filters. Nothing that I have done has changed anything except to remove the flattener. I have tried with no filter, which works as well, turning the filters around, painting the inside of the flattener and replacing the focuser among other things. I have another full frame flattener, a TS 2.5 inch that I will have to get some adapters made for so I can fit and test. At this stage, it will be imaging with out a flattener as I see no reason to persist. That will require a guider recal and possibly longer guide exposures to pick up guide stars as I notice the flattener can really help to resolve guide stars for OAG usage. Cheers and clears.
  5. I think the Dulux Dura Max will be the best. As for the painting itself, I have prepsol to clean the surfaces and yes, painting it with the spray can would be suicide. I am aware that replacing the flattener changes the focus point of the scope with the tube setup moving the focuser out which could possibly change where a reflection from something else might hit although I am sure that once you see the flattener internals it will be very easy to match up the off axis reflection with the components inside the flattener. Seeing the dot in the two images gave a pretty good hint once I looked in the flattener. Oh well, onward and upwards!
  6. William, are either of these suitable? I was thinking the Dulux Duramax by the cap colour? https://www.bunnings.com.au/dulux-duramax-300g-high-heat-enamel-spray-paint-black_p1400735 https://www.bunnings.com.au/white-knight-high-temp-300g-pot-belly-black-spray-paint_p1563023
  7. Thanks for all the info. I appreciate the feedback, links and advice, all good stuff! The sky magically cleared last night so I spent a few hours testing, swapping bits, etc. It is the flattener. If I put a tube in the imaging train where the flattener was, hey presto, no reflections. Refit the flattener, hello artifact, welcome back! I tested without the flattener, with the flattener and then without again on the same two objects that had been giving me trouble to ensure I had reasonably consistent results. I will try to photograph the flattener and the issue I think it is before I pull it apart and paint it inside and retest it. I am at work at the moment so I shall try to do that tonight. Now, about the tilt.....
  8. Thanks Whirlwind, my F/Touch came with the adapter to make it the same size as a WO end so I will sus this out!
  9. Thank you Olly for the image. I think at this stage, and I am hoping, that the issue is a reflection bouncing inside the flattener off the shiny black anodising. That may explain where it is showing up. Awaiting better skies, as always!
  10. I see. To be honest, I cannot remember when this first started. I have tried to think back and I can only say maybe since I replaced the QHY filters with the Baader ones. The two shots, L & G were taken straight after each other, both were guided 5 min sub frames. Is that enough to allow the camera setup inc flattener to move? Or could it be that one of the filters is not sitting square. Ive recently had them all out to check them. I have a straight nose piece that I have used previously with no issues so I will change to that and add a tether, also something else I have done previously. I have pulled the flattener out and I am waiting for decent skies to do some testing. I can see into the flattener and while the "through" surface is a flat grey (I would not say black) the inside barrel is anodised and is highly reflective and appears to give a rflection of the "through" barrel. If testing without the flattener is fruitful, I will have to find a way to dis-assemble the flattener to paint it or flock it some how. That sounds a logical next step in the process, thank you. I am not able to find any arrows on the filters or any marks saying which way round the go. I have used good lighting and a magnifying glass. I searched online and it said for the Baader filters, if there is no arrow, the most reflective side goes to the scope, the other side to the camera. I will double check this. I am using a QHY9 Camera and a QHY ultra slim filter wheel with a QHY OAG and QHY5LII guide cam. Thank you William for your thoughts and suggestions. I hope I can get it sorted soon.
  11. MeyGray3833

    Best autofocus software?

    I had trouble with getting SGP to work reliably. The trick was to use a digital vernier and actually measure how far 1000 steps moves the focuser in and out which will give you a very good average of your step size and also show you your backlash if using a rack and pinion focuser. Then you can set your amount of steps very accurately. I am running a Sharp Sky Pro set up on a 3.5 inch Feather Touch with step size of .00729mm (1000steps = 7.29mm). I set and tested at 25 steps, 9 data points with a star size of 10. I have since refined that to 30 steps with the same data points, etc. Also be aware that all autofocus routines will suffer in poor seeing and with fields lower in the sky. SGP has smart focus to try to help, I believe that Focus max has something compensatory as well. My other thought is, and I know that many people are using them with great success and this is my opinion only based on my experience, is a crayford focuser is not really a reliable device for accuarte focusng. A good rack and pinion unit with backlash compensation is a better mechanical choice straight up as it provides positive drive with no slippage.
  12. So far I have replaced the focuser with a Feathertouch that is flat blacked and baffled, as is the tube(FLT132), I have removed the filters and blackened their edges as they are the 36 mm unmounted type, with no success. I did some testing after fitting everything back and found that it was still there although it looks different in different filters. I did also notice a black dot in the ring of the reflection that is consistent across different filters. Could it be a screw hole or something, could I use this as something to guide me in what to check for? If the reflection is different in different filters, what would that say about where the reflection is originating from- before the filters and after the focuser? I have a WO Adj. PFlatIV in front of the filter wheel, may be it is in there. It also only seems to be when the scope is pointing more upright, which might indicate something falling over or flicking out when it starts to get vertical. I was going to get a ladder up there and see if I could see down there with a torch. I would definitely appreciate anyone's thoughts.
  13. MeyGray3833

    M77 and Friends

    Thanks to everyone that has liked the image, I'm glad you enjoyed the view. Demon and Alan, thanks for the affirmation of the field with a 5". It really does give a good perspective.
  14. MeyGray3833

    M77 and Friends

    Not really a 5 inch refractor target however; I was looking for something different to image. Now there is a super nova in M77. http://www.pbase.com/grahammeyer/image/168495360/original Details if they don not show up. Telescope: William Optics FLT132 Guide Scope: QHY OAG Camera: QHY9 Mono @ -20c Filter Wheel: QHY 7 position Ultra Slim Filters: QHY 36mm unmounted L R G B HA OIII SII Guide Camera: QHY5L-II Mount: AZ-EQ6 Mount Control: EQASCOM Focusing: SharpSky Pro and Sequence Generator Pro 3 (automated) Bahtinov Mask: No (initial focus) Capture Software: Sequence Generator Pro 3 Guiding Software: PHD2 Calibration and Stacking Software: PixInsight Processing Software: PixInsight Number and Type of Data Frames: L= 23X10 min, R= 11x7 min, G= 11x7 min, B= 11x7 min Ha= x , SII= x , OIII= x . Binning: 1x1 Total Image Time: 461 minutes Location: Lockleys Observatory B, Tanunda, Sth Australia Light Box by Exfso
  15. Hi, it is not in all of my images and only seems worse when the scope is pointed up nearer vertical. I'll have to pull the imaging train apart and have a look, it appears to be an internal reflection to me.

Important Information

By using this site, you agree to our Terms of Use.